Desmog for a 72--need help

[ar2stp48]

Sure this is a repeat question, but hope for a suggestion or two. Have a vac leak and will be chasing it this weekend. Would like to remove what little smog trash there is on a 72.
Main query: will the vac line that now goes from the carb to the "computer/ smog box" on the fender be routed to the vac port on distributer? Only way I see to get vac advance.
Seems more I drive this one the worse the vac leak gets so it is time to spend the time to find the problem.

 

[65swb45]

If your carb is a 72, then the carb port you speak of is on the outboard, secondary side. If you are running a 72 dizzy, then it is vacuum retard. The dizzy will run better disconnected UNLESS you can provide it with a vacuum signal that ONLY kicks in under heavy load. The secondary port provides a vacuum signal that is too strong for dizzy use; it will only drop out under the heaviest of loads.

Short answer: these two ports should NOT meet.

 

[ar2stp48]

Thanks, that is what I needed---short and to the point. Carb is original 72; so is entire cruiser. Bought it from original owner.
Will be disconnecting the vac line to dizzy and removing the other plumbing soon as I have a min. Glad the 72 doesnt have as much smog equip as the 78 does. Changed carbs on it and the desmog process was fairly easy.
Thanks again